8results about How to "Wide frequency range" patented technology

The application discloses a construction of a magneto-optical photonic crystal waveguide and a nontrivial one-way bulk state robust transmission method. The waveguide can excite a reverse-handed one-way boundary state and a one-way bulk state with reverse transmission simultaneously by parameter design of a square magneto-optical photonic crystal waveguide. The reverse-handed one-way boundary state is absorbed by upper and lower boundary conditions with scattering boundary conditions. Under the strong light transmission restriction of the square magneto-optical photonic crystal, the one-way bulk state is limited in the strip to transmit in one direction, thereby avoiding being absorbed, so that the waveguide forms a nontrivial one-way bulk state. The structure is topologically protected, and the nontrivial one-way bulk state robust transmission with complete one-way conductivity of the waveguide channel is realized. Further, the controllability of the nontrivial one-way bulk state transmission frequency can be realized by adjusting the magnetic field strength. The application has wide application prospects in the fields of robust energy transmission, optical communication technology and integrated photonic circuit.

The utility model belongs to electroacoustic transducer technical field discloses a moving coil type sound head and microphone. The moving coil type sound head includes shell, first sound pickup subassembly and second sound pickup subassembly, the inside of shell has acoustic cavity, shell has the sound inlet, acoustic cavity is connected with outside through sound inlet, first sound pickup subassembly includes first magnet and first sound film, is provided with first coil on first sound film, first sound film is opposite sound inlet and is arranged in acoustic cavity, first magnet is arranged in acoustic cavity, first sound film vibration drives first coil to move relatively first magnet and produces electric current, second sound pickup subassembly includes second magnet and second sound film, second magnet is arranged in acoustic cavity, second sound film and first sound film are along the propagation direction of sound wave in acoustic cavity and are spaced, are provided with second coil on second sound film, second sound film vibration drives second coil to move relatively first magnet and produces electric current. The moving coil type sound head improves the sensitivity of sound signal acquisition, can better capture and restore sound signal.

This utility model belongs to the field of smart ring technology, and relates to a small-sized haptic feedback device for rings. It includes a touch module, which is bonded to an FPC board inside the ring and fixed by a transparent encapsulant. The touch module includes a housing and a vibration component disposed within the housing. The vibration component includes piezoelectric ceramic and a protrusion. One end of the protrusion is bonded to an upper metal sheet on the piezoelectric ceramic, and the other end extends to the outside of the housing. The protrusion can move up and down under the action of the piezoelectric ceramic, transmitting the vibration of the vibration component to the skin of the finger. This utility model proposes a small-sized, low-power, high-precision haptic feedback solution suitable for smart rings, achieving efficient haptic feedback within a limited space while also considering wearing comfort and battery life.

The application provides an IGBT module electrical parameter on-line measuring device and method, the device comprises an interrupt control unit, a micro control unit and an analog-digital conversion unit, the micro control unit comprises a micro processing unit and a first timing unit, the application does not use FPGA, greatly reduces the hardware cost, reduces the power consumption and the circuit board area of on-line measuring device, and is convenient for integration.The application realizes the high-speed sampling of electrical parameters in the transient process of IGBT module turn-on or turn-off based on a first interrupt signal, realizes the low-speed sampling of electrical parameters in the steady state process of IGBT module turn-on or turn-off through a second interrupt signal, simultaneously realizes the high-speed and low-speed sampling of IGBT module turn-on or turn-off, the frequency range of sampling pulse is wide, and the data amount of electrical parameter sampling is greatly reduced, which provides a data basis for the fault diagnosis of power electronic equipment device level, on-line estimation of junction temperature and aging health index monitoring.

This invention discloses a method, apparatus, storage medium, and electronic device for improving the source bandwidth, comprising: acquiring seismic data from different energy levels using different source excitation methods; performing frequency analysis on the seismic data, statistically analyzing the energy distribution of each frequency component, and plotting spectral curves; normalizing the spectral curves to generate normalized amplitude spectra; determining the intersection point of the spectra of the two energy levels in the normalized amplitude spectrum, and using this intersection point as a boundary to extract the low-frequency region of the high-energy-level data and the high-frequency region of the low-energy-level data; assigning maximum amplitude values ​​to the frequency components of the extracted high-frequency and low-frequency regions respectively, and then superimposing them to generate broadband seismic data; and designing the source excitation ratio based on the generated data results. According to the method, apparatus, storage medium, and electronic device of this invention, seismic data can be superimposed to obtain seismic data that more closely approximates reality, and the excitation ratio can be precisely designed based on the seismic data.

The application discloses a same-frequency control strategy based on an H-MMC motor driving system; the motor driving system comprises a permanent magnet synchronous motor, an H-MMC and an alternating current power grid; firstly, a double-loop control is adopted to obtain motor-side d-axis and q-axis voltage reference values, a phase angle superposition amount is calculated in real time, and the motor-side d-axis and q-axis voltage reference values are added to a motor terminal voltage phase angle obtained by a phase-locked loop to obtain a final motor phase angle so as to adjust the motor-side three-phase voltage reference values in real time; a double-loop control is adopted to obtain a grid-side three-phase voltage reference value; hierarchical capacitor voltage balance control and circulating current control are adopted to obtain a neutral point voltage reference value and a bridge arm voltage reference value superposition amount; voltage modulation wave superposition amount of a sub-module voltage is obtained through voltage balance control; finally, driving signals of each sub-module are generated through CPS-PWM after the modulation wave of each sub-module voltage is calculated according to the above control; through real-time adjustment of the phase angle of the motor-side three-phase voltage reference values, the application can realize that the bridge arm differential frequency power approaches to 0, and can effectively suppress the capacitor voltage fluctuation of the sub-module without increasing circulating current or injecting reactive power, so that the stable operation of the system under the same frequency condition is realized; and the application has the advantages of simple control and small loss.

The invention relates to the technical field of antennas, in particular to a liquid crystal material-based variable double-ring multi-bit coding RCS (radar cross section) reduction metasurface, which consists of five layers of structures, namely an upper dielectric substrate, a tuning metal patch, a liquid crystal material, a lower dielectric substrate and a metal floor from top to bottom. The array is composed of N * N units, the metal patch layer is subjected to a plurality of slotting treatments based on a traditional double-ring shape, and a plurality of communication branch treatments are added to the metal patch layer, so that the surface current and electric field distribution of the metal patch layer is changed, more resonance modes are introduced, and the metasurface unit can respond to a wider frequency range. In order to solve the problems that a traditional RCS reduction metasurface is single in performance and poor in environment adaptability, the metasurface unit reflection phase is regulated and controlled in a target frequency band by loading a liquid crystal material, and multi-bit coding is achieved by changing the liquid crystal dielectric constant, so that the scattering characteristic of an array plane can be reconstructed, and the RCS is reduced by more than 10 dB.

The invention relates to an audio enhancement method and device and an earphone. The audio enhancement method comprises the following steps: acquiring an air conduction audio signal and a bone conduction audio signal; acquiring a first audio feature of the air conduction audio signal and a second audio feature of the bone conduction audio signal; performing feature extraction on the bone conduction audio signal through a trained feature extraction model to obtain a voiceprint feature of the bone conduction audio signal; inputting the voiceprint feature of the bone conduction audio signal, the first audio feature and the second audio feature into a trained amplitude prediction model to obtain a predicted amplitude; and enhancing the audio based on the predicted amplitude to obtain a target audio signal. According to the invention, the dual model mechanism fuses the advantages of bone conduction and air conduction, so that the obtained target audio signal does not lose the frequency band, the noise reduction is realized, and the audio quality is improved.